Friday, September 12, 2008

Obesity? Don't just blame it on your Genes!

Vigorous physical activity can help even people genetically prone to obesity keep the weight off, US researchers said on Monday. A study among a group of Amish people found those who had an obesity-related gene called FTO but were very physically active weighed about the same as others who did not carry the gene.

"When we looked at the Amish who were the most active, there is suddenly no effect of that gene," said Dr Soren Snitker of the University of Maryland. The findings may help inform the debate over whether changes in diet or physical activity will make the biggest difference in fighting obesity.

Consumer groups have pushed for laws such as a moratorium on new fast-food restaurants in certain Los Angeles neighbourhoods, while the food industry often maintains that a lack of exercise is more to blame.

Snitker and Evadnie Rampersaud of the University of Miami were looking to see if physical activity might offset the effects of obesity associated with the FTO gene, found in more than half of all people of European descent. People with two copies of the FTO gene on average weigh nearly 3kg more.

The researchers found those who were less active and had the FTO gene variant were significantly more likely to be overweight or obese. But among the most physically active, the FTO gene made no difference.